Methods to reduce frequency of diesel particulate filter regeneration

Abstract

The present disclosure relates to a method of reducing regeneration frequency of a diesel particulate filter in a vehicle combusting diesel fuel. The method includes combusting a diesel fuel in a vehicle engine having a diesel particulate filter and wherein the diesel particulate filter requires regeneration thereof. The diesel fuel has less than about 50 ppmw of sulfur and one or more select additives to reduce a measured frequency of regeneration of the diesel particulate filter.

What is claimed is: 
     
       1. A method of reducing measured regeneration frequency of a diesel particulate filter in a vehicle combusting diesel fuel, the method comprising:
 (a) combusting a diesel fuel in a vehicle engine, wherein the vehicle includes a diesel particulate filter associated with the engine and wherein the diesel particulate filter requires regeneration thereof, the diesel fuel having less than about 50 ppm of sulfur and a diesel fuel additive including
 (i) a hydrocarbyl substituted dicarboxylic anhydride derivative prepared by reacting a hydrocarbyl-substituted succinic acylating agent with an amine, polyamine, or alkyl amine having one or more primary, secondary, or tertiary amino groups; 
 (ii) a quaternary ammonium internal salt obtained from amines or polyamines that is substantially devoid of any free anion species comprising a compound of formula (VI): 
 
 
       
         
           
           
               
               
           
         
       
       wherein
     R and R′ are independently alkylene linkers having 1 to 10 carbon atoms;   R 12  is a hydrocarbyl group or optionally substituted hydrocarbyl group, or an aryl group or optionally substituted aryl group;   R 13  is independently a linear or branched C1 to C4 alkyl group; and   R 14  is a hydrogen or a C1 to C4 alkyl group; and     (iii) a thiazole, triazole, thiadiazole, a tolytriazole, or combinations thereof;   
 (b) regenerating the diesel particulate filter while combusting the diesel fuel; and 
 (c) comparing the frequency of regeneration of the diesel particulate filter when combusting the diesel fuel comprising the additives with the frequency of regeneration of the diesel particulate filter when combusting a diesel fuel which is devoid of the additives; wherein the frequency of regenerations per 1000 miles of the diesel particulate filter when combusting the diesel fuel comprising the additives is lower than a frequency of regenerations per 1000 miles of the diesel particulate filter when combusting a diesel fuel in the engine devoid of the additives. 
 
     
     
       2. The method of  claim 1 , wherein the hydrocarbyl substituted dicarboxylic anhydride derivative of additive (i) has a structure of Formula II 
       
         
           
           
               
               
           
         
       
       wherein R 4  is a hydrocarbyl group and R 5  is hydrogen, an alkyl group, an aryl group, —OH, —NHR 5′ , or a polyamine and wherein R5′ is a hydrogen or an alkyl group. 
     
     
       3. The method of  claim 2 , wherein the additive of Formula II includes a hydrocarbyl substituted succinimide derived from ethylene diamine, diethyelene triamine, triethylene tetraamine, tetraethylene pentamine, pentaethylene hexamine, N,N′-(iminodi-2,1,ethanediyl)bis-1,3-propanediamine and combinations thereof. 
     
     
       4. The method of  claim 2 , wherein R 4  in the compound of Formula II is a hydrocarbyl group having a number average molecular weight from about 450 to about 3,000 and R 5  is derived from tetraethylene pentamine and derivatives thereof. 
     
     
       5. The method of  claim 1 , wherein R and R′ are independently alkylene linkers having 1 to 3 carbon atoms and R 12  is a C8 to C20 hydrocarbyl group. 
     
     
       6. The method of  claim 1 , Wherein R′ includes a methylene linker. 
     
     
       7. The method of  claim 1 , wherein R 13  is a methyl group. 
     
     
       8. The method of  claim 1 , wherein R 12  is derived from an oleyl fatty acid. 
     
     
       9. The method of  claim 1 , wherein the diesel fuel includes about 5 ppmw to about 150 ppmw of additive (i) and about 1 ppmw to about 35 ppmw of additive (ii). 
     
     
       10. The method of any of  claim 1 , wherein the diesel fuel includes less than about 20 weight percent of bio-generated diesel fuel additives selected from the group consisting of fatty acid methyl esters, hydrotreated vegetable oil, soybean methyl esters, palm methyl esters, and combinations thereof. 
     
     
       11. The method of any of  claim 1 , wherein the regeneration occurs when the engine injects excess diesel fuel into a cylinder to increase the exhaust gas temperature to exceed a predetermined temperature and reacts with a catalyst (DOC) causing an elevated temperature across the catalyst and into the diesel particulate filter. 
     
     
       12. The method of  claim 11 , wherein the regeneration is measured when the exhaust gas stream exceeds about 480° C. 
     
     
       13. The method of  claim 1 , wherein the reduction in regeneration frequency occurs immediately upon combusting the diesel fuel having the one or more additives. 
     
     
       14. The method of  claim 1 , wherein the regeneration frequency per 1000 miles is about 0.5 to about 20 percent lower than the regeneration frequency per 1000 miles of a diesel fuel devoid of the one or more additives.